Typically, molten metal is pumped into casting machines and the like by electromagnetic pumps. Many of these pumps utilize the Faraday-Lorentz principles in which electrical energy is converted into mechanical energy. An example of an electromagnetic pump employing powerful neo-magnets is described in U.S. Pat. No. 6,732,890, which is hereby incorporated by reference in its entirety. As will be appreciated, such pumps are generally quite effective at pumping, braking and metering molten metal.
Known electromagnetic pumps typically rely on DC current coming into contact with molten metal through electrodes. To deliver the current, the electrodes are in direct contact with the molten metal. In this regard, electrodes generally extend into a pump conduit through which the molten metal passes. In a known pump, electrodes fit within elongated apertures machined into opposite sides of a molten metal conduit. The electrodes include passageways to accommodate a cooling apparatus that includes tubing through which a liquid coolant passes. Though effective, it is desirable to employ a pump in which there is no contact between electrodes, or any other portion of the pump, and the molten metal. It is also desirable to have molten metal contact only the conduit of a pump.
In view of the above, it is a general object to provide a pump for the pumping of molten metal. In particular, the present invention provides a magnetic induction pump having a magnetic induction rotor for pumping molten metal without the need for direct mechanical or electrical contact between components of the pump and the molten metal.